The exemplary embodiments relate to a projector.
A related art projector is shown in FIGS. 10A–10C. FIG. 10A is a view showing an optical system of the related art projector. FIGS. 10B and 10C are views of assistance in explaining a problem with similar related art projectors.
A projector 900A has liquid crystal devices 400R, 400G, 400B used as electro-optic modulators that are a hold type display device having a brightness characteristic as shown in FIG. 10B. Therefore, unlike a CRT, which is an impulse type display device having a brightness characteristic as shown in FIG. 10C, the projector 900A has a problem in that smooth moving-picture display can not be achieved because of a persistence of vision. The persistence of vision is described in, for example: “Image Quality of Moving-picture Display on Hold Type Display,” EID99–10, pp. 55–60, The Institute of Electronics, Information and Communication Engineers Technical Report (June 1999).
Another related art projector is shown in FIGS. 11A–11C. FIG. 11A is a view showing an optical system of the related art projector. FIGS. 11B and 11C are views of assistance in showing an optical shutter used for the related art projector.
The problem described above is solved in the projector 900B as follows. As shown in FIG. 11A, optical shutters 420R, 420G, 420B are disposed on light-incident sides of the liquid crystal devices 400R, 400G, 400B respectively so as to cut off light intermittently. In other words, the shutters are arranged so that the persistence of vision is relaxed, whereby smooth and good-quality moving-picture display can be attained (see e.g. JP-A-2002-148712, esp. FIGS. 1–7).
However, the latter related art projector still has a problem in that the use of light efficiency is reduced significantly because the optical shutters cut off light intermittently.